Seroprevalence, Blood Chemistry, and Patterns of Canine Parvovirus, Distemper Virus, Plague, and Tularemia in Free-Ranging Coyotes (Canis latrans) in Northern New Mexico, USA.

Wildlife diseases have implications for ecology, conservation, human health, and health of domestic animals. They may impact wildlife health and population dynamics. Exposure rates of coyotes (Canis latrans) to pathogens such as Yersinia pestis, the cause of plague, may reflect prevalence rates in both rodent prey and human populations. We captured coyotes in north-central New Mexico during 2005-2008 and collected blood samples for serologic surveys. We tested for antibodies against canine distemper virus (CDV, Canine morbillivirus), canine parvovirus (CPV, Carnivore protoparvovirus), plague, tularemia (Francisella tularensis), and for canine heartworm (Dirofilaria immitis) antigen. Serum biochemistry variables that fell outside reference ranges were probably related to capture stress. We detected antibodies to parvovirus in 32/32 samples (100%), and to Y. pestis in 26/31 (84%). More than half 19/32 (59%) had antibodies against CDV, and 5/31 (39%) had antibodies against F. tularensis. We did not detect any heartworm antigens (n = 9). Pathogen prevalence was similar between sexes and among the three coyote packs in the study area. Parvovirus exposure appeared to happen early in life, and prevalence of antibodies against CDV increased with increasing age class. Exposure to Y. pestis and F. tularensis occurred across all age classes. The high coyote seroprevalence rates observed for CPV, Y. pestis, and CDV may indicate high prevalence in sympatric vertebrate populations, with implications for regional wildlife conservation as well as risk to humans via zoonotic transmission.

Learning from history in the midst of the COVID-19: epidemics/pandemics of antiquity up to the fall of the Western Roman Empire.

When humans discovered agriculture and livestock, they ceased to be nomads and began to settle in towns until they created large cities. From the first human settlements in Egypt, Mesopotamia, and the Anatolian Peninsula, populations were exposed and susceptible to new infectious agents, leading to epidemics and pandemics. Great civilizations emerged, such as Egypt, the land of Hatti, Israel, Greece, Carthage, and Rome, among others. Contact between different populations through wars or maritime trade is well documented and has been described as a source of epidemics throughout history. Epidemics described as plagues or pestilences, such as those of Egypt, the Hebrews, or the Hittites, are based on biblical texts or evidence such as tablets or hieroglyphic writings. We also reviewed classical books by authors such as Homer, Aeschylus, Herodotus of Halicarnassus, Thucydides, Diodorus Siculus, Dionysius of Halicarnassus, Titus Livius, Suetonius, and others; and described all epidemics/pandemics chronologically. This article describes the epidemics/pandemics for which there is written evidence from ancient Egypt to the fall of the Roman Empire. We should not be surprised when new epidemics/pandemics appear as causes of political and economic collapse, as this has been common throughout history, decimating, blocking, or even destroying cultures and civilizations repeatedly.

Cuando el hombre descubrió la agricultura y la ganadería, dejó de ser nómada y empezó a asentarse en pueblos hasta crear grandes ciudades. Desde los primeros asentamientos humanos en Egipto, Mesopotamia y la península de Anatolia, las poblaciones estuvieron expuestas y susceptibles a nuevos agentes infecciosos, dando lugar a epidemias y pandemias. Aparecieron grandes civilizaciones como Egipto, la Tierra de Hatti, Israel, Grecia, Cartago y Roma, entre otras. El contacto entre las distintas poblaciones a través de las guerras o el comercio marítimo está muy bien establecido y descrito como focos de epidemias a lo largo de la historia. Las epidemias descritas como plagas o pestilencias, como las que ocurrieron a los egipcios, los judíos, o los hititas, se describen con base en textos bíblicos o mediante evidencias como tablillas o escritos jeroglíficos. También revisamos libros clásicos de autores como Homero, Esquilo, Herodoto de Halicarnaso, Tucídides, Diodoro Sículo, Dionisio de Halicarnaso, Tito Livio, Suetonio, entre otros. Este artículo describe cronológicamente todas las epidemias/pandemias de las que existe evidencia a través de la escritura desde el antiguo Egipto hasta la caída del Imperio Romano. No debemos sorprendernos cuando aparecen nuevas epidemias/pandemias como causantes del colapso político y económico, ya que ha sido algo común a lo largo de la historia, diezmando, bloqueando o incluso destruyendo culturas y civilizaciones reiteradamente.

Comparative sequence analysis elucidates the evolutionary patterns of Yersinia pestis in New Mexico over thirty-two years.

Background: Yersinia pestis, a Gram-negative bacterium, is the causative agent of plague. Y. pestis is a zoonotic pathogen that occasionally infects humans and became endemic in the western United States after spreading from California in 1899. Methods: To better understand evolutionary patterns in Y. pestis from the southwestern United States, we sequenced and analyzed 22 novel genomes from New Mexico. Analytical methods included, assembly, multiple sequences alignment, phylogenetic tree reconstruction, genotype-phenotype correlation, and selection pressure. Results: We identified four genes, including Yscp and locus tag YPO3944, which contained codons undergoing negative selection. We also observed 42 nucleotide sites displaying a statistically significant skew in the observed residue distribution based on the year of isolation. Overall, the three genes with the most statistically significant variations that associated with metadata for these isolates were sapA, fliC, and argD. Phylogenetic analyses point to a single introduction of Y. pestis into the United States with two subsequent, independent movements into New Mexico. Taken together, these analyses shed light on the evolutionary history of this pathogen in the southwestern US over a focused time range and confirm a single origin and introduction into North America.

Performance assessment of a new indirect rapid diagnostic test for plague detection in humans and other mammalian hosts.

Plague is a flea-borne zoonosis that affects a wide range of mammals and still causes outbreaks in human populations yearly across several countries. While crucial for proper treatment, early diagnosis is still a major challenge in low- and middle-income countries due to poor access to laboratory infrastructure in rural areas. To tackle this issue, we developed and evaluated a new Fraction 1 capsular antigen (F1)-based rapid diagnostic test (RDT) as an alternative method for plague serological diagnosis and surveillance in humans and other mammals. In this study, 187 serum samples from humans, dogs, rodents and rabbits were retrospectively assessed using the plague RDT method. To calculate its performance, results were compared to those obtained by traditional hemagglutination (HA) and ELISA, which are well-established methods in the plague routine serodiagnosis. Remarkably, the results from RDT were in full agreement with those from the ELISA and HA assays, resulting in 100% (CI 95% = 95.5-100%) of sensitivity and 100% (CI 95% = 96.6-100%) of specificity. Accordingly, the Cohen's Kappa test coefficient was 1.0 (almost perfect agreement). Moreover, the RDT showed no cross-reaction when tested with sera from individuals positive to other pathogens, such as Y. pseudotuberculosis, Yersinia enterocolitica, Anaplasma platys, Ehrlichia canis and Leishmania infantum. Although preliminary, this study brings consistent proof-of-concept results with high performance of the Plague RDT when compared to HA and ELISA. Although further human and animal population-based studies will be necessary to validate these findings, the data presented here show that the plague RDT is highly sensitive and specific, polyvalent to several mammal species and simple to use in field surveillance or point-of-care situations with instant results.

Healthiness and disease in Marmato gold mines during the 19th century: Between the smallpox plague and the War of a Thousand Days / [Salubridad y enfermedad en las minas de oro de Marmato en el siglo XIX: entre la epidemia de viruela y la guerra de los mil días].

Mining has had a great influence on human societies permeating the riches of the soil and culture in equal proportion. This has led to profound changes in the individuals dedicated to this work and the locations where it takes place. In this historical review, we describe the socio-cultural and health characteristics, as well as the diseases associated with gold mining in Marmato (Caldas) during the 19th century. Poor salubrity conditions and tropical and infectious diseases were constant during the whole century.

La minería ha tenido una gran influencia en las sociedades humanas, permeando por igual las riquezas del suelo y la cultura, lo que ha tenido profundas implicaciones para los individuos dedicados a esta labor y para los lugares en los que se lleva a cabo. En el presente artículo, se describen las características socioculturales y de sanidad, así como las enfermedades más frecuentes en las minas de oro de Marmato (Caldas) durante el siglo XIX. Las precarias condiciones de salubridad y las enfermedades tropicales infecciosas persistieron en la población durante todo el siglo.

Spatiotemporal analysis of bubonic plague in Pernambuco, northeast of Brazil: Case study in the municipality of Exu.

Along with other countries in America, plague reached Brazil through the sea routes during the third pandemic. A brief ports phase was followed by an urban phase that took place in smaller inland cities and finally, it attained the rural area and established several foci where the ecological conditions were suitable for its continued existence. However, the geographic dispersion of plague in Brazil is still poorly studied. To better understand the disease dynamics, we accessed satellite-based data to trace the spatial occurrence and distribution of human plague cases in Pernambuco, Northeastern Brazil and using the municipality of Exu as study case area. Along with the satellite data, a historical survey using the Plague Control Program files was applied to characterize the spatial and temporal dispersion of cases in the period of 1945-1976. Kernel density estimation, spatial and temporal clusters with statistical significance and maximum entropy modeling were used for spatial data analysis, by means of the spatial analysis software packages. The use of geostatistical tools allowed evidencing the shift of the infection from the urban to the wild-sylvatic areas and the reemergence of cases after a period of quiescence, independent of the reintroduction from other plague areas.

Rodent hosts and flea vectors in Brazilian plague foci: a review.

Plague, caused by the Yersinia pestis bacterium, has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Ceará to the Southeastern State of Minas Gerais and another separated area at the State of Rio de Janeiro. This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019. Furthermore, we discuss how the interaction between Y. pestis and some rodent host species may play a role in the disease dynamics. The absence of human cases nowadays in Brazil does not mean that it was eradicated. The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike, alternating epidemics with decades of quiescence. Hence, it remains an important epidemic disease of global concern. The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.

De la Peste Antonina a la Peste de Cipriano: alcances y consecuencias de las pestes globales en el Imperio Romano en el siglo III dC / From the Antonine Plague to the Cyprian Plague: scopes and consequences of global plagues in the Roman Empire in the 3rd century AD

Resumen El Imperio Romano sufrió entre el siglo II y III dos grandes pestes, la Peste Antonina, de la cual existe bibliografía, y la Peste de Cipriano, que es menos conocida. Como una visión de conjunto, ambas pandemias se asemejan a la crisis que en el 2020 el coronavirus está generando en muchos aspectos de la vida humana. Este artículo se centra en el impacto que la peste de Cipriano tuvo en el contexto de la crisis del siglo III; su mortalidad se estima entre 10-20% de la población en los lugares afectados y finalmente sus efectos generaron varias de las condiciones necesarias para la transición del mundo antiguo al medieval. Se trata de comprender cómo el ciclo de pestes que va desde el siglo II al siglo III cambió la fisonomía del mundo romano y que lecciones nos entrega la historia 1700 años después.

Abstract Between the 2nd and 3rd centuries the Roman Empire suffered two great plagues, the Antonine Plague, of which there is a bibliography, and the lesser known Plague of Cyprian. As an overview, both pandemics resemble the crisis that in 2020 the Coronavirus is generating in many aspects of human life. This article focuses on the impact that the Cyprian plague had in the context of the crisis of the third century, its mortality is estimated between 10-20% of the population in the affected places, finally its effects generated several of the necessary conditions for the transition from the ancient to the medieval world. It is about understanding how the cycle of plagues that went from the 2nd century to the 3rd century changed the appearance of the Roman world and what lessons history gives us 1700 years later.

An Evaluation of the Flea Index as a Predictor of Plague Epizootics in the West Nile Region of Uganda.

Plague is a low incidence flea-borne zoonosis that is often fatal if treatment is delayed or inadequate. Outbreaks occur sporadically and human cases are often preceded by epizootics among rodents. Early recognition of epizootics coupled with appropriate prevention measures should reduce plague morbidity and mortality. For nearly a century, the flea index (a measure of fleas per host) has been used as a measure of risk for epizootic spread and human plague case occurrence, yet the practicality and effectiveness of its use in surveillance programs has not been evaluated rigorously. We sought to determine whether long-term monitoring of the Xenopsylla flea index on hut-dwelling rats in sentinel villages in the plague-endemic West Nile region of Uganda accurately predicted plague occurrence in the surrounding parish. Based on observations spanning ~6 yr, we showed that on average, the Xenopsylla flea index increased prior to the start of the annual plague season and tended to be higher in years when plague activity was reported in humans or rodents compared with years when it was not. However, this labor-intensive effort had limited spatial coverage and was a poor predictor of plague activity within sentinel parishes.

[From the Antonine Plague to the Cyprian Plague: Scopes and consequences of global plagues in the Roman Empire in the 3rd century AD.] / De la Peste Antonina a la Peste de Cipriano: Alcances y consecuencias de las pestes globales en el Imperio Romano en el siglo III d.C.

Between the 2nd and 3rd centuries the Roman Empire suffered two great plagues, the Antonine Plague, of which there is a bibliography, and the lesser known Plague of Cyprian. As an overview, both pandemics resemble the crisis that in 2020 the Coronavirus is generating in many aspects of human life. This article focuses on the impact that the Cyprian plague had in the context of the crisis of the third century, its mortality is estimated between 10-20% of the population in the affected places, finally its effects generated several of the necessary conditions for the transition from the ancient to the medieval world. It is about understanding how the cycle of plagues that went from the 2nd century to the 3rd century changed the appearance of the Roman world and what lessons history gives us 1700 years later.

Principales pandemias en la historia de la humanidad / Major pandemics in the history of mankind

Introducción: Se describen las principales pandemias en la historia de la humanidad desde a.n.e. hasta la más reciente causada por el coronavirus SARS-CoV-2. Objetivo: Examinar las principales pandemias en la historia de la humanidad y su repercusión en la salud pública, ámbito social y perspectivas de la actual pandemia de la COVID-19 en el desarrollo de la sociedad. Métodos: Se revisaron las publicaciones sobre el tema en español e inglés en bases de datos de PubMed, Google Scholar, SciELO y Latindex desde el 2000 hasta al 25 de mayo 2020. Resultados: Se describen los aspectos más sobresalientes de las epidemias causadas por viruela, peste bubónica, cólera, VIH/sida. gripes y la actual producida por el coronavirus SARS-CoV-2, atendiendo a su aparición, duración en años, fallecidos, localización mundial, países más afectados e impacto en la sociedad y ámbito sanitario. Se exponen las perspectivas sociales determinadas por la pandemia de la COVID-19. Conclusiones: Se examinan los rasgos sobresalientes, en especial las pérdidas de vidas humanas en las principales pandemias que han azotado a la humanidad, desde a.n.e. hasta la más reciente causada por el coronavirus SARS-CoV-2. La sociedad en su momento actual se enfrenta a incertidumbres y retos sociales, económicos, culturales, éticos, sanitarios y existenciales, provenientes de las implicaciones que está teniendo la pandemia de la COVID-19, lo que determinará consecuencias para la salud y la vida humana. Esta pandemia es mucho más que una crisis sanitaria(AU)

Introduction: This work describes the major pandemics in the history of mankind from B.C. until the most recent caused by the coronavirus SARS-CoV-2. Objective: To examine the major pandemics in the history of mankind and their impact on public health, social scopes and prospects of the current pandemic of COVID-19 in the development of mankind. Methods: There were reviewed publications on the subject in Spanish and English in databases of PubMed, Google Scholar, SciELO and Latindex from 2000 to 25 May, 2020. Results: There is a description of the most important aspects of epidemics caused by smallpox, bubonic plague, cholera, HIV/AIDS, influenzas and the current one produced by the coronavirus SARS-CoV-2, on the basis of their onsets, duration in years, amount of deceased, world location, most affected countries and impact on society and the health field. The social perspectives determined by the pandemic of COVID-19 are presented. Conclusions: There was an study on the outstanding features, especially the loss of human lives in the major pandemics that have plagued mankind, from B.C. until the most recent caused by the coronavirus SARS-CoV-2. The global society at present time is facing uncertainties and challenges of social, economic, cultural, ethical, health and existential kind coming from the implications caused by the COVID-19 pandemic, which will determine consequences for human health and life. This pandemic is much more than a health crisis(AU)

La peste bubónica en Cuba. Apuntes históricos / Bubonic plague in Cuba. Historical notes

Introducción: La peste bubónica afectó a gran parte del mundo en la primera mitad del siglo xx, causando desde pequeños brotes a grandes epidemias. En Cuba se presentó en dos oportunidades, en 1912 y en 1914, causando alguna morbimortalidad. Objetivo: Rescatar la historia de las epidemias de peste bubónica en Cuba. Metodología: Cualitativa, utilizando como métodos teóricos el histórico-lógico y el análisis documental. Se revisaron estadísticas en el Departamento de Estadísticas y Registros Médicos del Ministerio de Salud Pública, artículos de la época, directrices y planes de enfrentamiento a la epidemia orientados por el Departamento Nacional de Sanidad, de la Secretearía de Sanidad y Beneficencia, e informes redactados por los sanitaristas que trabajaron en su control. Resultados: En 1912 existieron brotes en La Habana, Santiago de Cuba y Pinar del Río, importada de las Islas Canarias. Durante la segunda epidemia en 1914, erradicada al año siguiente, se produjeron 68 casos y 23 fallecidos. Se diseñó una estrategia de lucha que incluyó, desde el ingreso y aislamiento de los sospechosos, vigilancia de los residentes en la zona, recogida de ratas, hasta desinfección, saneamiento y desratización de la zona afectada. Conclusiones: Las medidas tomadas fueron oportunas y eficientes, controlando la epidemia. No se produjeron más casos desde julio de 1915(AU)

Introduction: The bubonic plague affected much of the world in the first half of the twentieth century, causing from small outbreaks to large epidemics. In Cuba, it appeared twice in 1912 and in 1914 causing some morbidity and mortality. Objective: To rescue the history of bubonic plague's epidemics in Cuba. Methodology: Qualitative, using as theoretical methods the historical- logic and the documentary analysis. Statistics were reviewed in the Department of Statistics and Medical Records of the Ministry of Public Health, in articles of the time, in guidelines and plans to confront the epidemic established by the National Department of Health of the Secretariat of Health and Charity, and also reports written by the health workers who participated in the control strategies of this disease. Results: In 1912, there were outbreaks in Havana, Santiago de Cuba and Pinar del Rio imported from the Canary Islands. In the second epidemic in 1914 that was eradicated in 1915, there were 68 cases and 23 deaths. A control strategy was designed, which included the entry and isolation of the suspects, surveillance of the residents in the area, collection of rats, disinfection, sanitation and deratization of the affected area. Conclusions: The measures taken were timely and efficient for controlling the epidemic. No more cases have occurred since July, 1915(AU)

A single introduction of Yersinia pestis to Brazil during the 3rd plague pandemic.

Yersinia pestis was introduced to Brazil during the third plague pandemic and currently exists in several recognized foci. There is currently limited available phylogeographic data regarding Y. pestis in Brazil. We generated whole genome sequences for 411 Y. pestis strains from six Brazilian foci to investigate the phylogeography of Y. pestis in Brazil; these strains were isolated from 1966 to 1997. All 411 strains were assigned to a single monophyletic clade within the 1.ORI population, indicating a single Y. pestis introduction was responsible for the successful establishment of endemic foci in Brazil. There was a moderate level of genomic diversity but little population structure among the 411 Brazilian Y. pestis strains, consistent with a radial expansion wherein Y. pestis spread rapidly from the coast to the interior of Brazil and became ecologically established. Overall, there were no strong spatial or temporal patterns among the Brazilian strains. However, strains from the same focus tended to be more closely related and strains isolated from foci closer to the coast tended to fall in more basal positions in the whole genome phylogeny than strains from more interior foci. Overall, the patterns observed in Brazil are similar to other locations affected during the 3rd plague pandemic such as in North America and Madagascar.

Fumigating the Hygienic Model City: Bubonic Plague and the Sulfurozador in Early-Twentieth-Century Buenos Aires.

The 1899/1900 arrival of bubonic plague in Argentina had thrown the model status of Buenos Aires as a hygienic city into crisis. Where the idea of foreign threats and imported epidemics had dominated the thinking of Argentina's sanitarians at that time, plague renewed concerns about hidden threats within the fabric of the capital's dense environment; concerns that led to new sanitary measures and unprecedented rat-campaigns supported by the large-scale application of sulphur dioxide. The article tells the story of early twentieth-century urban sanitation in Buenos Aires through the lens of a new industrial disinfection apparatus. The Aparato Marot, also known as Sulfurozador was acquired and integrated in the capital's sanitary administration by the epidemiologist José Penna in 1906 to materialise two key lessons learned from plague. First, the machine was supposed to translate the successful disinfection practices of global maritime sanitation into urban epidemic control in Argentina. Second, the machine's design enabled public health authorities to reinvigorate a traditional hygienic concern for the entirety of the city's terrain. While the Sulfurozador offered effective destruction of rats, it promised also a comprehensive - and utopian - disinfection of the whole city, freeing it from all imaginable pathogens, insects as well as rodents. In 1910, the successful introduction of the Sulfurozador encouraged Argentina's medico-political elite to introduce a new principle of 'general prophylaxis'. This article places the apparatus as a technological modernisation of traditional sanitary practices in the bacteriological age, which preserved the urban environment - 'el terreno' - as a principal site of intervention. Thus, the Sulfurozador allowed the 'higienistas' to sustain a long-standing utopian vision of all-encompassing social, bodily and political hygiene into the twentieth century.

Identifying the social and environmental determinants of plague endemicity in Peru: insights from a case study in Ascope, La Libertad.

BACKGROUND: Plague remains a public health problem in specific areas located in Bolivia, Brazil, Ecuador and Peru. Its prevention and control encompasses adequate clinical management and timely laboratory diagnosis. However, understanding communities' interaction with its surrounding ecosystem as well as the differences between community members and institutional stakeholders regarding the root causes of plague might contribute to understand its endemicity. We aim at bridging the traditionally separate biological and social sciences by elucidating communities' risk perception and identifying knowledge gaps between communities and stakeholders. This approach has been used in other areas but never in understanding plague endemicity, nor applied in the Latin American plague context. The objectives were to identify (i) plague risk perception at community level, (ii) perceived social and environmental determinants of plague endemicity, and (iii) institutions that need to be involved and actions needed to be taken as proposed by stakeholders and community members. The study was performed in 2015 and took place in Ascope rural province, La Libertad Region, in Peru, where the study areas are surrounded by intensive private sugarcane production. METHODS: We propose using a multi-level discourse analysis. Community households were randomly selected (n = 68). Structured and semi-structured questionnaires were applied. A stakeholder analysis was used to identify policy makers (n = 34). In-depth interviews were performed, recorded and transcribed. Descriptive variables were analyzed with SPSS®. Answers were coded following variables adapted from the Commission on Social Determinants of Health and analyzed with the assistance of ATLAS.ti®. RESULTS: Results showed that risk perception was low within the community. Policy-makers identified agriculture and sugarcane production as the root cause while community answers ranked the hygiene situation as the main cause. Stakeholders first ranked governmental sectors (education, housing, agriculture and transport) and the community prioritized the health sector. Social surveillance and improving prevention and control were first cited by policy-makers and community members, respectively. CONCLUSIONS: The determinants of plague endemicity identified by the two groups differed. Similarly, actions and sectors needed to be involved in solving the problem varied. The gaps in understanding plague root causes between these two groups might hinder the efficiency of current plague prevention and control strategies.

Seroprevalence and spatial distribution dynamics of Yersinia pestis antibodies in dogs and cats from plague foci in the State of Ceará, Northeastern Brazil

Abstract INTRODUCTION: In Brazil, the plague is established in several foci located mainly in the northeastern part of the country, where it alternates between active and quiescent periods. These foci in the State of Ceará have high epidemiological importance. In addition to other plague detection activities, plague areas can be monitored through serological surveys of dogs and cats (domestic carnivores), which, following feeding on plague-infected rodents, can develop mild to severe forms of the disease and produce long-lasting antibodies. This study aimed to characterize the circulation dynamics and spatial distribution of Yersinia pestis antibodies in dogs and cats in plague foci areas of Ceará. METHODS: An ecological study was conducted to analyze the temporal series and spatial distribution of secondary data obtained from domestic carnivore serum surveillance in Ceará's plague areas from 1990 to 2014. RESULTS: Joinpoint analysis revealed that the overall trend was a reduction in antibody-positive animals. The mean proportion of antibody-positivity during the whole study period was 1.5% (3,023/203,311) for dogs, and 0.7% (426/61,135) for cats, with more than 4% antibody-positivity in dogs in 1997 and 2002. Antibody titers ranging from 1/16 to 1/64 were frequent. Despite fluctuations and a significant reduction, in recent years, there were antibody-positive animals annually throughout the study period, and the localities containing antibody-positive animals increased in number. CONCLUSION: Yersinia pestis is actively circulating in the study areas, posing a danger to the human population.